The present invention relates to an improved device, for application to a splitting machine, designed for processing corrugated board material, to make product packaging boxes and the like.
As is known, a splitting machine is designed for making suitable split and ribbed arrangements in the corrugated paperboard material, which is supplied, with a flat arrangement, at one end of the splitting machine.
The corrugated board portions, in particular, are trimmed, ribbed and die-cut, so as to be adapted for bending to make packaging boxes.
Prior paperboard material splitting or die-cutting machines, however, are affected by several drawbacks, mainly related to the machine portions which are used for forming, at one side end, the box joining flap.
Such a joining flap, more specifically, is a paperboard material side flap, which is used for closing the box by glueing or seaming.
Such a glueing or seaming operation, in particular, is at present performed by mechanical means, i.e. mechanical devices including a plurality of rotary blades, which are mounted on a top cutting blade supporting disc.
The cutting blades are arranged with a suitably slanted or inclined arrangement with respect to the cutting blade supporting disc and cooperate with abutment rings rotatively driven together with a bottom counter-splitting disc.
Thus, prior paperboard material splitting or die-cutting machines require a lot of labour consuming adjusting operations, since the mentioned bottom abutment rings, which are usually made of a polyurethane material, are quickly worn.
In a further prior embodiment, the mentioned bottom abutment rings are made of a hardened steel material.
In this case, on the other hand, it is necessary to manually adjust the cutting depth of the cutting blades, depending on the thickness of the paperboard material being processed.
Such an adjusting operation is necessary for preventing the joining flap cutting blades from being quickly worn, as well as to prevent the cutting blade holder shafts and bearings from being also quickly worn because of a comparatively high operating load.
Yet another prior paperboard material splitting or die-cutting machine provides to use top joining flap cutting blades, which are mounted in supporting recesses therefor, including a plurality of resilient spring or pressing-elements, urging the cutting blades so as to provide a suitable cutting pressure.
In this case too, the joining flap cutting blades work in cooperation with bottom abutment ring elements, made of a hardened steel material, mounted on a counter-splitting member.
While the latter paperboard material splitting machine is preferred with respect to the other above disclosed splitting or die-cutting machine, it, however, presents the drawback that it cannot be easily fitted, in its cutting pressure, to the different thicknesses of paperboard materials to be split or cut.
For example, as a joining flap is to be cut from a paperboard material having a thickness of 10 mm, then it would be necessary to provide a resilient spring adapted to apply a suitable cutting pressure, which must be comparatively high.
On the other hand, as, by the same machine, a paperboard material having a thickness of only 3 mm must be cut, then it is necessary to cause the steel ring element mounted on the bottom abutment splitting element to be approached, since it is necessary to drive towards one another the disc elements provided for allowing the paperboard material to be properly fed.
Under the above mentioned conditions, the joining flap cutting blades would excessively cut through the paperboard material because of a greater pressure of the spring, with a consequent quick wearing of the cutting blades.
Moreover, said cutting blades, also in this case, would apply an excessively great load on the cutting blade bearing shafts and bearing assemblies, thereby causing either a temporaneous or permanent flexure of said shafts and a quick wearing of the bearings.
Moreover, all the above disclose paperboard material splitting or die-cutting machines are affected by further drawbacks.
One of the latter is that as packages without joining flaps must be made, then it is necessary to manually disassemble the joining flap cutting blades, and then assemble them again for processing boxes including the joining flaps.
Furthermore, if a joining flap having a length greater than the height of a closed box must be made, then it is necessary to manually drive the cutting blades, with consequent complex operations to be performed by skilled operators.
Thus, the aim of the present invention is to provide such an improved device for forming joining flaps in box die-cutting or splitting machines, which allows to automatize and greatly simplify all the adjusting operations, so as to reduce to a minimum the wearing of the cutting blades.
Within the scope of the above mentioned aim, a main object of the present invention is to provide such an improved device which, for operation, does not require to disassemble the cutting blades for making boxes either including or not the joining flaps, or boxes including a greater length joining flap.
Another object of the present invention is to provide such an improved device allowing to fully eliminate any stresses from the cutting blade supporting bearings and rollers.
In fact, the joining flap cutting blades are mounted on a dedicated mounting assembly, located outside of the paperboard material splitting or die-cutting machine.
Thus, such a dedicated and outside joining flap cutting assembly does not require any manual adjusting for use, with the exception of the adjustment operations required for fitting the processed paperboard material thicknesses.
Moreover, the subject improved assembly allows to easily make joining flaps of any desired lengths, which could not be obtained in the above disclosed prior devices.
In fact, in the latter, the maximum length of the joining flap depends on the peripheral extension of the cutting blade supporting disc thereon are mounted the joining flap cutting blades.
Moreover, the device according to the invention provides the further advantage that it can be applied to all the existing paperboard material splitting or die-cutting machine, and, more specifically, at the paperboard material inlet and output sides thereof.
The device according to the present invention, moreover further comprises a trimming assembly for precisely trimming the processed paperboard material and for allowing a suitable fragmentation of the trim arrangement to be easily made.
The latter feature, in particular, would greatly facilitate the removal of the paperboard material trimmed waste thereby preventing any jamming from occurring.
The device for trimming and fragmentating the processed paperboard material does not require any pressure adjustments, with respect to the trim breaking blade, while providing all the disclosed operating advantages of the joining flap cutting assembly.